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Numerical Simulations of Coastal Overwash Using A Phase-Averaged Wave−Current−Sediment Transport Model

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China Ocean Engineering 2022年第2期36卷 191-207页

作者： LI Song-zhe ji Chao ZHANG qing-he CHEN Tong-qing State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300350China Key Laboratory of Engineering Sediment Tianjin Research Institute for Water Transport EngineeringMinistry of TransportTianjin 300456China

Coastal overwash is a natural phenomenon that commonly occurs during storm events and can cause considerable changes in nearshore morphology within a short time.In this study,a complete set of empirical overwash transport algorithms is developed and introduced into a phase-averaged wave-current-sediment transport coupling model that integrates the Finite-Volume Community Ocean Model(FVCOM)and the Simulating Waves Nearshore(SWAN)model.The resulting morphological evolution model can simulate coastal overwash.Validation against the data obtained from multiple sets of laboratory overwash experiments demonstrates that the model performs relatively well in simulating morphological changes caused by runup overwash and inundation overwash under different hydrodynamic and beach profile conditions.The sensitivity of each empirical coefficient in the overwash transport algorithms is comprehensively analyzed.The effects of each coefficient on the output of the model are discussed,and a recommended value range is provided for each coefficient.

关键词： wave-current coupling phase-averaged model overwash wave runup morphological evolution

Snow features on sea ice in the western Arctic Ocean during summer 2016

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International Journal of Digital Earth 2021年第10期14卷 1397-1410页

作者： Qing Ji Xiaoping Pang Xi Zhao Ruibo Lei Chinese Antarctic Center of Surveying and Mapping Wuhan UniversityWuhanPeople’s Republic of China Polar Research of China ShanghaiPeople’s Republic of China

Arctic sea ice and its snow cover are important components of the cryosphere and the climate system.A series of in situ snow measurements were conducted during the seventh Chinese Arctic expedition in summer 2016 in the western Arctic Ocean.In this study,we made an analysis of snow features on Arctic sea ice based on in situ observations and the satellite-derived parameter of snow grain size from MODIS spectral reflectance data.Results indicate that snow depth on Arctic sea ice varied between 19 and 241 mm,with a mean value of 100 mm.The mean density of the snow was 340.4 kg/m^(3)during the expedition,which was higher than that reported in previous literature.The measurements revealed that a depth hoar layer was widely developed in the snow,accounting for 30%∼50%of the total snow depth.The equivalent snow grain size was small on the surface and large at the bottom in snow pits.The average relative error between MODIS-derived snow grain size and in situ measured surface snow grain size is 14.6%,indicating that remote sensing is a promising method to obtain large-scale information of snow grain size on Arctic sea ice.

关键词： Snow cover snow grain size snow stratigraphy remote sensing

Nomogram for predicting early complications after distal gastrectomy

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World Journal of Gastrointestinal Surgery 2023年第11期15卷 2500-2512页

作者： Biao Zhang qing Zhu Zhi-Peng ji Department of Gastrointestinal Surgery Second Hospital of Shandong UniversityJinan 250033Shandong ProvinceChina

BACKGROUND Reducing or preventing postoperative morbidity in patients with gastric cancer(GC)is particularly important in perioperative treatment plans.AIM To identify risk factors for early postoperative complications of GC post-distal gastrectomy and to establish a nomogram prediction model.METHODS This retrospective study included 131 patients with GC who underwent distal gastrectomy at the Second Hospital of Shandong University between January 2019 and February 2023.The factors influencing the development of complications after distal gastrectomy in these patients were evaluated using univariate and multivariate logistic regression analysis.Based on the results obtained,a predictive nomogram was established.The nomogram was validated using internal and external(n=45)datasets.Its sensitivity and specificity were established by receiver operating characteristic curve analysis.Decision curve(DCA)analysis was used to determine its clinical benefit and ten-fold overfitting was used to establish its accuracy and stability.RESULTS Multivariate logistic regression analysis showed that hypertension,diabetes,history of abdominal surgery,and perioperative blood transfusion were independent predictors of postoperative complications of distal gastrectomy.The modeling and validation sets showed that the area under the curve was 0.843[95%confidence interval(CI):0.746-0.940]and 0.877(95%CI:0.719-1.000),the sensitivity was 0.762 and 0.778,respectively,and the specificity was 0.809 and 0.944,respectively,indicating that the model had good sensitivity and specificity.The C-indexes of the modeling and validation datasets were 0.843(95%CI:0.746-0.940)and 0.877(95%CI:0.719-1.000),respectively.The calibration curve(Hosmer Lemeshow test:χ^(2)=7.33)showed that the model had good consistency.The results of the DCA analysis indicated that this model offered good clinical benefits.The accuracy of 10-fold cross-validation was 0.878,indicating that the model had good accuracy and stability.CONCLUSION The nomogram prediction model based on

关键词： Blood transfusion Gastroenterostomy Nomograms Postoperative complications Stomach neoplasms Risk factors

Characterization of sea ice and its snow cover in the Arctic Pacific sector during the summer of 2016

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Acta Oceanologica Sinica 2021年第1期40卷 33-42页

作者： Qing Ji Ying Liu Xiaoping Pang Yue Pan Xi Zhao Chinese Antarctic Center of Surveying and Mapping Wuhan UniversityWuhan 430079China Key Laboratory of Polar Surveying and Mapping Ministry of Natural ResourcesWuhan 430079China School of Resource and Environmental Sciences Wuhan UniversityWuhan 430079China

A comprehensive analysis of sea ice and its snow cover during the summer in the Arctic Pacific sector was conducted using the observations recorded during the 7th Chinese National Arctic Research Expedition(CHIANRE-2016)and the satellite-derived parameters of the melt pond fraction(MPF)and snow grain size(SGS)from MODIS data.The results show that there were many low-concentration ice areas in the south of 78°N,while the ice concentration and thickness increased significantly with the latitude above the north of 78°N during CHIANRE-2016.The average MPF presented a trend of increasing in June and then decreasing in early September for 2016.The average snow depth on sea ice increased with latitude in the Arctic Pacific sector.We found a widely developed depth hoar layer in the snow stratigraphic profiles.The average SGS generally increased from June to early August and then decreased from August to September in 2016,and two valley values appeared during this period due to snowfall incidents.

关键词： sea ice snow cover melt pond fraction snow grain size Arctic Pacific sector

Retrieval of snow depth on Antarctic sea ice from the FY-3D MWRI data

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Acta Oceanologica Sinica 2023年第12期42卷 105-117页

作者： Zhongnan Yan Xiaoping Pang Qing Ji Yizhuo Chen Chongxin Luo Pei Fan Zeyu Liang Chinese Antarctic Center of Surveying and Mapping Wuhan UniversityWuhan 430079China Key Laboratory of Polar Surveying and Mapping Science Ministry of Natural ResourcesWuhan 430079China

The snow depth on sea ice is an extremely critical part of the cryosphere.Monitoring and understanding changes of snow depth on Antarctic sea ice is beneficial for research on sea ice and global climate change.The Microwave Radiation Imager(MWRI)sensor aboard the Chinese FengYun-3D(FY-3D)satellite has great potential for obtaining information of the spatial and temporal distribution of snow depth on the sea ice.By comparing in-situ snow depth measurements during the 35th Chinese Antarctic Research Expedition(CHINARE-35),we took advantage of the combination of multiple gradient ratio(GR(36V,10V)and GR(36V,18V))derived from the measured brightness temperature of FY-3D MWRI to estimate the snow depth.This method could simultaneously introduce the advantages of high and low GR in the snow depth retrieval model and perform well in both deep and shallow snow layers.Based on this,we constructed a novel model to retrieve the FY-3D MWRI snow depth on Antarctic sea ice.The new model validated by the ship-based observational snow depth data from CHINARE-35 and the snow depth measured by snow buoys from the Alfred Wegener Institute(AWI)suggest that the model proposed in this study performs better than traditional models,with root mean square deviations(RMSDs)of 8.59 cm and 7.71 cm,respectively.A comparison with the snow depth measured from Operation IceBridge(OIB)project indicates that FY-3D MWRI snow depth was more accurate than the released snow depth product from the U.S.National Snow and Ice Data Center(NSIDC)and the National Tibetan Plateau Data Center(NTPDC).The spatial distribution of the snow depth from FY-3D MWRI agrees basically with that from ICESat-2;this demonstrates its reliability for estimating Antarctic snow depth,and thus has great potential for understanding snow depth variations on Antarctic sea ice in the context of global climate change.

关键词： snow depth Antarctic sea ice passive microwave FY-3D

Probabilistic Optimal Power Flow Considering the Dependence of Multiple Wind Farms Using Pair Diffusive Kernel Copula

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CSEE Journal of Power and Energy Systems 2023年第5期9卷 1641-1654页

作者： Tianyao ji Yantai Lin Yuzi jiang Mengshi Li qing-Hua Wu the School of Electric Power Engineering South China University of TechnologyGuangzhou 510641China

As wind farms are commonly installed in areas with abundant wind resources,spatial dependence of wind speed among nearby wind farms should be considered when modeling a power system with large-scale wind power.In this paper,a novel bivariate non-parametric copula,and a bivariate diffusive kernel(BDK)copula are proposed to formulate the dependence between random variables.BDK copula is then applied to higher dimension using the pair-copula method and is named as pair diffusive kernel(PDK)copula,offering flexibility to formulate the complicated dependent structure of multiple random variables.Also,a quasi-Monte Carlo method is elaborated in the sampling procedure based on the combination of the Sobol sequence and the Rosen-blatt transformation of the PDK copula,to generate correlated wind speed samples.The proposed method is applied to solve probabilistic optimal power flow(POPF)problems.The effectiveness of the BDK copula is validated in copula definitions.Then,three different data sets are used in various goodness-of-fit tests to verify the superior performance of the PDK copula,which facilitates in formulating the dependence structure of wind speeds at different wind farms.Furthermore,samples obtained from the PDK copula are used to solve POPF problems,which are modeled on three modified IEEE 57-bus power systems.Compared to the Gaussian,T,and parametric-pair copulas,the results obtained from the PDK copula are superior in formulating the complicated dependence,thus solving POPF problems.

关键词： Bivariate diffusive kernel copula correlated wind speeds pair diffusive kernel copula probabilistic optimal power flow quasi-Monte Carlo Rosenblatt transformation

Relationship between hydrogenation degree and pyrolysis performance of jet fuel

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CHINESE JOURNAL OF CHEMICAL ENGINEERING 2024年第4期68卷 35-42页

作者： Liu, qing jia, Tinghao Pan, Lun Zou, ji-Jun Zhang, Xiangwen Tianjin Univ Sch Chem Engn & Technol Key Lab Green Chem & Technol Tianjin 300072 Peoples R China Haihe Lab Sustainable Chem Transformat Tianjin 300192 Peoples R China Tianjin Univ Zhejiang Inst Ningbo 315201 Peoples R China Zhejiang Univ Coll Chem & Biol Engn Zhejiang Prov Key Lab Adv Chem Engn Manufacture Te Hangzhou 310027 Peoples R China

Understanding the relationship between the chemical composition and pyrolysis performance of endothermic hydrocarbon fuel (EHF) is of great significance for the design and optimization of advanced EHFs. In this work, the effect of deep hydrogenation on the pyrolysis of commercial RP-3 is investigated. Fuels with different hydrogenation degrees were obtained by the partially and completely catalytic hydrogenation and their pyrolysis performances were investigated using an apparatus equipped with an electrically heated tubular reactor. The results show that with the increase of hydrogenation degree, fuel conversion almost remains constant during the pyrolysis process (500-650 degrees C, 4 MPa); however, the heat sink increases slightly, and the anti-coking performance significantly improves, which are highly related to their H/C ratios. Detailed characterisations reveal that the difference of the pyrolysis performance can be ascribed to the content of aromatics and cycloalkanes: the former are prone to initiate secondary reactions to form coking precursors, while the latter could act as the hydrogen donor and release hydrogen, which will terminate the radical propagation reactions and suppress the coke deposition. This work should provide the guidance for upgrading EHFs by modulating the composition of EHFs. (c) 2024 The Chemical Industry and Engineering Society of China, and Chemical Industry Press Co., Ltd. All rights reserved.

关键词： Fuel Pyrolysis Hydrogenation Deposition ANTI-COKING PERFORMANCE THERMAL-DECOMPOSITION SUPERCRITICAL CONDITIONS MODEL COMPOUNDS CATALYSTS DODECANE ALKANES

Surface charge transfer doping of graphene using a strong molecular dopant CN6-CP

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Chinese Chemical Letters 2023年第3期34卷 553-556页

作者： Xiaojuan Dai Liyao Liu Zhen ji qing Meng Ye Zou Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Organic SolidsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China

Surface charge transfer doping of graphene plays an important role in graphene-based electronics due to its simplicity,high doping efficiency,and easy-controllability.Here,we demonstrate the effective surface charge transfer hole doping of graphene by using a strong p-type molecular dopant hexacyanotrimethylene-cyclopropane (CN6-CP).The CN6-CP exhibits a very high intrinsic work function of 6.37 e V,which facilitates remarkable electron transfer from graphene to CN6-CP as revealed by in situ photoelectron spectroscopy investigations.Consequently,hole accumulation appears in the graphene layer at the direct contact with CN6-CP.As evidenced by Hall effect measurements,the areal hole density of graphene significantly increased from 8.3×10^(12)cm^(-2) to 2.21×10^(13)cm^(-2) upon 6 nm CN6-CP evaporation.The CN6-CP acceptor with strong p-doping effect has great implications for both graphene-based and organic electronics.

关键词： Graphene Surface charge transfer doping Molecular dopant CN6-CP Hall effect

Ziyin Huatan Recipe, a Chinese herbal compound, inhibits migration and invasion of gastric cancer by upregulating RUNX3 expression

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Journal of Integrative Medicine 2022年第4期20卷 355-364页

作者： Shang-jin Song Xuan Liu Qing Ji Da-zhi Sun Li-juan Xiu jing-yu Xu Xiao-qiang Yue Department of Traditional Chinese Medicine Changzheng HospitalNaval Medical UniversityShanghai 200003China Strategic Support Force Xingcheng Special Duty Sanatorium Xingcheng 125100Liaoning ProvinceChina Cancer Institute Shuguang HospitalShanghai University of Traditional Chinese MedicineShanghai 201203China

Objectives: Ziyin Huatan Recipe(ZYHT), a traditional Chinese medicine comprised of Lilii Bulbus, Pinelliae Rhizoma, and Hedyotis Diffusa, has shown promise in treating gastric cancer(GC). However, its potential mechanism has not yet been clearly addressed. This study aimed to predict targets and molecular mechanisms of ZYHT in treating GC by network pharmacology analysis and to explore the role of ZYHT in GC both in vitro and in vivo.Methods: Targets and molecular mechanisms of ZYHT were predicted via network pharmacology analysis. The effects of ZYHT on the expression of metastasis-associated targets were further validated by Western blot and quantitative real-time polymerase chain reaction. To explore the specific molecular mechanisms of the effects of ZYHT on migration and invasion, the runt-related transcription factor 3(RUNX3) gene was knocked out by clustered regularly interspaced short palindromic repeats/Cas9, and lentiviral vectors were transfected into SGC-7901 cells. Then lung metastasis model of GC in nude mice was established to explore the anti-metastasis effect of ZYHT. Western blot and immunohistochemistry were used to explore the impact of ZYHT on the expression of metastasis-related proteins with or without RUNX3 gene.Results: The network pharmacology analysis showed that ZYHT might inhibit focal adhesion, migration,invasion and metastasis of GC. ZYHT inhibited the proliferation, migration and invasion of GC cells in vitro via regulating the expression of metastasis-associated targets. Knocking out RUNX3 almost completely reversed the cell phenotypes(migration and invasion) and protein expression levels elicited by ZYHT.In vivo studies showed that ZYHT inhibited the metastasis of GC cells to the lung and prolonged the survival time of the nude mice. Knocking out RUNX3 partly reversed the metastasis of GC cells to the lung and the protein expression levels elicited by ZYHT.Conclusion: ZYHT can effectively inhibit the invasion and migration of GC in vitro and in vivo, and its molecular mechanism m

关键词： Ziyin Huatan Recipe Gastric cancer Traditional Chinese medicine Metastasis Runt-related transcription factor 3